Compounded by an increase in the detection of asymptomatic cases that might have previously gone undetected, with proactive testing for holiday travel, parties and other get-togethers having jumped, the number of new Covid-19 cases in San Francisco hit a record daily high of 794 on December 21, which equates to an all-time high case rate of 91 new cases per 10,000 residents, a number that’s likely to be upwardly adjusted over the next week.
The previous daily high for new cases, save for 562 new cases flagged on December 20, was 558 cases or roughly 64 cases per 10,000 residents on January 4 of this year (followed by a Delta-driven spike of 446 cases, or 51 cases per 10,000 residents, on July 29).
And the six neighborhoods with the highest cumulative case rates over the past two months were the Marina (362 new cases/143 new cases per 10,000 residents); Russian Hill (234/129); Hayes Valley (224/114); South Beach/Financial District (234/109); Mission Bay (144/109) and Pacific Heights (251 new cases/103 new cases per 10,000 residents), representing a dramatic shift from earlier in the pandemic when Bayview Hunters Point, the Tenderloin, Visitacion Valley and the Mission had the highest concentration of cases.
UPDATE (12/28): Having been upwardly adjusted, the number of new Covid-19 cases in San Francisco actually hit a record daily high of 860 on December 21, which was surpassed by a new all-time high of 894 cases on 12/22 and then 964 new cases, and counting, on December 23.
At the same time, the 7-day average number of new daily cases, which hit a new all-time high of 395 on 12/21, was up to nearly 600 on 12/23, having peaked at 310 for Delta and 373 in the first (Alpha) wave.
UPDATE (12/29): Having been upwardly adjusted, the number of new Covid-19 cases in San Francisco actually hit a record daily high of 1,054, and still counting, on December 23 and the 7-day average ticked over 600 on December 24.
On a positive note, while the precipitous drop in the number of new cases identified on December 24 was primarily a factor of a drop in the number of tests administered on Christmas Eve, the preliminary test positivity rate was down to 7.1 percent, versus 11.6 percent on December 23. But hospitalizations have started ticking up as well.
UPDATE (12/30): The record number of new Covid-19 cases detected in San Francisco on December 23 has ticked up to 1,075 for a 7-day average of 603 cases per day. The 7-day average through 12/24 has ticked up to 629. And unfortunately, the test positivity rate on December 23 has been upwardly adjusted to 11.8 percent with a 12.5 percent positivity rate on December 24.
UPDATE (01/03/22): Having hit a record-high of 1,093 on December 23, the number of new Covid-19 cases detected in San Francisco hit a new all-time high of 1,485 (and still counting) on December 27. And despite a drop in testing on Christmas, Christmas Eve and the day after Christmas as well, the 7-day average number of daily new cases detected in San Francisco ticked over 900 on December 28 with a test positivity rate of 18.3 percent on December 27.
UPDATE (01/04): S.F. Will Soon Average Over 1,500 New COVID Cases Per Day